Hi, I believe that there’s a bug in how unpack over symlinks is handled. On extract newer records in tar stream should by default overwrite older extracted items. In GNU tar this doesn’t work if older record is a symlink which target starts with root (/).
This is tested on version 1.30 built from source, archive dated 2017-12-17 06:43. Consider three cases: case 1: (tar tv output) lrwxrwxrwx admin/admin 0 2018-05-17 15:27 foo -> bar -rw-r--r-- admin/admin 6 2018-05-17 15:27 foo (tar x, then find -ls) 266605 4 drwxr-xr-x 2 admin admin 4096 May 17 15:40 unpack1 266606 4 -rw-r--r-- 1 admin admin 6 May 17 15:27 unpack1/foo case 2: (tar tv output) lrwxrwxrwx admin/admin 0 2018-05-17 15:25 foo -> /bar -rw-r--r-- admin/admin 6 2018-05-17 15:25 foo (tar x, then find -ls) 266607 4 drwxr-xr-x 2 admin admin 4096 May 17 15:40 unpack2 266608 0 lrwxrwxrwx 1 admin admin 4 May 17 15:25 unpack2/foo -> /bar ( case 3: (tar tv output) lrwxrwxrwx admin/admin 0 2018-05-17 15:39 foo -> dir/bar -rw-r--r-- admin/admin 6 2018-05-17 15:39 foo (tar x, then find -ls) 266612 4 drwxr-xr-x 2 admin admin 4096 May 17 15:40 unpack3 266613 4 -rw-r--r-- 1 admin admin 6 May 17 15:39 unpack3/foo I expect all of them upon extraction produce a regular file, but case 2 leaves symlink instead. You can find more listings as well as comparison against bsdtar here: https://gist.github.com/artyom/926ec9c49a2077f2820053274f0b1b16
